Circuit-breaker.



O. AALBORG. CIRCUIT BREAKER.

APPLICATION FILED JULY 3, 1955. 1,099,332. Patented June 9,1914.

2 SHEETSSHEET 1.

I b F n! GA KW L- U ATTORNEY O. AALBORG. CIRCUIT BREAKER. APPLICATIONFILED JULY 3, 1905.

- Patented June 9, 1914.

2 SHEETi -SHfiET 2,

- operating handle,

The bracket 2 comprises the panel '1 by bolts 1 CHRISTIAN :AALBORG, 0FWILKINSBURG,

PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIC 86 MANUFACTURINGCOMPANY. A COBYEOBAI'ION OF PENNSYL- VANIA.

CIRCUIT-BREAKER.

Specification of'Letters Patent.

Patented June 5?, M91 4;.

Application filed July 3, 1905. Serial No. 268,266. v

To all whom it may concern Be it known that I, CHRISTIAN AALnono, acitizen of the Unit-ed States, and a resident of \Vilkinsburg, in thecounty of Allegheny and State of Pennsylvania, have invented a new anduseful Improvement-in Circuit-Biteakers of which the following is aspecification.

My invention relates to circuit-breakers, and it has for its object toprovide a handoperated and automatically released circuitbreaker withmeans for preventing the holding of the breaker in its closed positionunder overload or other predetermined conditions, that shall be simplein construction and effective in operation and that shall not interferewith the normal operation of the breaker The circuit breaker of myinvention is providedwith a special construction which prevents it fromremaining in its closed po-' sition under overload conditions, eventhough a retaining'foree be'appliedito the so that protection of thecircuit and its-translating devices is insured and is dependent onlyupon-the automatic tripping device.

A further advantage of the breaker of my invention lies in the fact thatit'may be hand-operated under normal conditions to open and close thecircuit, at the will of the operator.

In the, accompanying drawings, Figure 1 is a side elevation and Fig. 2 a"front elevation of a circuit-braker constructed in ac cordanoe with myinvention and shown in closed position. Fig. 3 is a side elevation ofthe circuit-breaker shown in Figs. 1 and 2, the movable member beingshown in its open position. 1 v I Although my invention is shown only inconnection with a breaker which is autornatica l'y released -underoverload condi tions, 1t. may

be applied to breakers which are adaptedfor operation under otherpredetermined conditions.

The principal stationary parts of the circuit-breaker illustrated are anon-conductin a main contact terminal bloek 3, an arebreaking terminalblock t and a: conducting stri or p ate- 5 between the blocks 3 and 45.

a pair of substantially parallel plates 2 that are secured. to

and project outwardly slab or panel 1, a supporting-bracket 2,-

thercirom. Pins 9,15 and 25am so supported by the plates 2 that they areparallel to the plane of the slab l and serve as axes for the movableparts of the 'lu'eakcr. A two-part lever S is pivotally mounted near oucend on the pin 9 and is provided with a pin S at its outer end whichties the two parts of the lever together and supports main and auxiliarycontact-bearing members 7 and ll that are mounted thereon. lhc member '7is prevented from rotating about the pin 8 as an and the member ll islimited in its rotation about the same axis by a pin 13 which passesthrough a projection for the former and through a relatively large hole12 in the latter. 3 A. spring ll is interposed betwee-uzthe members 7and 1,1 in order to tilt the auxiliary clontact-hearing members forwardwhen the breaker is open.

An operating handle 'l-Il: is attached to a double forked operatinglever 14F which is pivotally mounted, on studs or rivets 15 by which itsouter prongs are attached to the outer extremities of the bracket plate2.

he inner prongs of vthe lever 14 are materially longer than the outerprongs and are connected with the pin 8? at the extremityof the lever Sby means of :1V link 16 and a. pair of shorter parallel links 17 and 18which are constructed to act as a single connecting link under normalconditions and to assume the position shown in Fig. 1 when the breakeris closed and that shown in 3 when the breaker is open.

A laminated currmt-carrying contact member 6 is attached to the member 7and is resilient by reason of its structure so that it will compensatefor a certain wear which occurs on the contact surface.

An auxiliary contact member 10 which be constructed of carbon or othersuitable material is adapted to coiiperate with" the stationary arebreaking contact member 4. .A conducting: plate 10* is attached to themember 10 by means of a hollow rivet or stud '10 and 'is' supported,adjustably atseat itself when it engages the stationary member loot'aehed. to the member 11 by side projections ais The links 17 and 1 areconnected to the extremity of the handle lever itat one end by a pin I land. at the other end are coir ncctcd to substantially the middle pointof thc liuk 16 by a pin lb. The tree end of the link 16 is provided witha. p1ojection, ll, that may be engaged by a portion ol the trippingmechanism, and with a pr jection 2) which normally engages theconnecting pin l-lr by which the l nks 17' and l9 are attached to theoperating lever ll.

The, tripping nmchauism comprises a framc'Q'l, upon. which is adjustablymounted a wcig'l'lt Q2 and to which a U-shaped armature 23 ofmagnetizable material is at: tached. The frame 91 suspended from atripping lever 2-1, that is rotatably mounted upon a pin or rod 3 withwhich the sup porting bracket 2 is provided. it magnetizing winding iscoiled ab ut a magnetizas blc core 27, which surrounds the shaft 9.

The inner end of the coil or spiral is electrically connected with theside plates 2 of the bracket. by means of the bushing or core 27 and itsouter end is connected rectly (as shown in Fig. l), to a main terminalstud 7 of the breaker. It will be observed that when the breaker isclosed an electric circuit may be established from stationary contactmember 3 through movable member 6, shunt (3, bracket plates 2, oushing2'? and the coil 26 to terminal i hen the current flowing through thecircuit exceeds a predcterniined amount, the armature 23 is attracted bythe core I? and the free end of the trip1')ing lever 21: is moved intoengagcmcnt with he projection 19 01 the connect ing link 16. When thisoccurs the breaker is thrown, by a spring 28, to the position indicatedby broken lines in Fig. .Vhen the breaker is closed, it is retained inthis position normally by a projection 29 which is attached to thehandle lever and engages the pin on the bracket 9., since the pivot pins14; and 16 are substantially in the same straight line. When the breakeris operated by hand to open the circuit, the lever 16 and the connectinglinks 17 and 18 retain the same relative positions, while the joint bctween the links 17 and 18 and the handle lever 14* is broken to form anacute angle, as shown in full lines in Fig. 3.

When the free end of the tripping lever 24 is brought into engagementwith the projection 19 of the link 16, the joint between the connectinglinks 17 and 18 and the link 16 is broken, as well as the joint betweenthe links 17 and 1S and the handle lever l t", and the breaker assumesthe position indicated by broken lines in Fig. 3. It is obvious that ifthe handle is held in. the position shown in Fig. 1, it will not preventthe opening of the circuit by the tripping mechanism.

I desire and intend to include within the.

scope of my invention all variations from 'ot' said links to releasesaid switch member independently of the operating lever.

, Q. in a circuit-tncaker, the combination with a movable switch member.an operating lever tulerumed at an intermediate point in its length, anda connecting and locking means between the switch member and one end ofthe operating lever, which comprises a relatively long link and a pairor short links, of means -tor engaging the free end of the long link toopen the circuit-breaker independently of the ope ating lever.

23. in a circuit-breaker. the combination with a movable switch member,an operating lever tulcrumed at an intermediate point in its length, arelatively long link connected to the switch member and a pair of shortlinks between one end of the operating lever and an intermediate poi utin the long link, of automatic tri iiping means which is dependent'uponpredetermined circuit conditions for engaging the free end of the longlink to open the circuit-breaker independently of the opera ting lever.

4-. Tn a circuit-breaker, the combination with a movable switch member,an operating lever fulcrumcd at an intermediate point in its length, arelatively long link connected to the switch member and a pair of shortlinks between one end of the opcrating lever and an intermediate pointinthe long link, of an electromagnet which is responsive topredetermined conditions in the circuit, and an armature for trippingsaid links to open the circuit-breaker independently of the op cratinglever.

5-1n a circuit-breaker, the combination with a stationary contactmember, a movable member provided with a laminated contact terminal anda resiliently supported arcbrcaking contact terminal, an operatinghandlc and an automatic tripping mechanism,- of means for connecting themovable contact member and the operating handle lever to:

gether, said means comprising a long link having oncend pivotallyconnected to the movable contact member and a pair of parallel linkspin-connected to said long link substantially at its middle point andalso pin-connected to one end of the operating handle lever.

in a circu t-breaker, the. combination with a stationary contact memberand a supporting bracket, :1 morable contact member, a tripping deviceand an operating handle pivotally mounted upon said bracket, of meansfor mechanically connecting the mo\' able contact member and theoperating handle together, said means comprising a long link whichis'pin-conneoted at one end to the movable contact member and a pair ofpar- 10 allel links which are pivotally mounted upon one end of theoperating handle and are pin-connected to said long link substantiallyat its middle point.

7. In a circuit breaker, the combination 15 with a movable switch memberan operating CH'THSTIAN AALBORG.

LID

Witnesses lVM. BRADSHAW, BIRN'EY :EIINES.

